Before I built my own tower out of wood, I found the best way to swap hoses in the metal ones was to disassemble the faucet shank, put the stuff that goes on the inside of the tower (hose clamp, nut, washer) over the hose, while holding it so that stuff doesn't fall down into the tower. Then push the hose through the faucet hole, assemble, insert in tower, loosely place nut and washer, tighten hose clamp, tighten the other stuff. PIA, but it works.